For hundreds of years, musical instructors and musical-instruction-book authors have manually prepared altered versions of musical selections to facilitate instruction of students with varying levels of skill and musical competence and for arranging musical selections for different types and numbers of musical instruments. By altering musical selections, music teachers and authors of musical instruction books can tailor well known and musically pleasing pieces to various skill-levels of different classes of students, as well as to skill-levels to which the music teachers and authors of musical instruction books are attempting to elevate a particular class of students. Variations of musical selections featuring a range of complexity levels can provide a useful vehicle for musical instruction that allows a student to experience the pleasure of performing musical pieces without also frustrating the student by demanding greater skill or musical competence than the student can be expected to display at a particular point in time. Such variation groups can also offer a pedagogical benefit. Instruction books typical of the art are usually based on a linear progress model—the student learns one piece and moves on to the next selection. In contrast to this, the proposed method of generating variation groups featuring a range of complexity levels based on a single composition allow the student to undertake new challenges with consistent and fine control over the nature and extent of those challenges. Because the variation groups are based on the same underlying composition, the underlying musical elements are common to all variations and can be carried from one variation to the next to an extent determined by user preference. For example, the method allows a user to proceed from a variation with simplified melody and bass, to a subsequent variation with identical bass, and melody with a small increase in technical challenge.
Until now, the generation of variations of musical selections with ranges of difficulties for performance has been largely a tedious, manual, arbitrary and imperfect process. In general, an instructor or musical-instruction-book author can provide, at best, one or only a few variations of a particular musical selection, and the granularity of skill-level addressed by the variations is thus rather large. A musical student is therefore constrained to selecting music from among an often narrow selection of musical pieces at any particular desired skill-level. Musical teachers, authors of musical-instruction-books, and other musical professionals have recognized the need for a means to generate a range of variations directed to a corresponding range of skill-levels for a large number of different musical pieces that is relatively inexpensive and efficiently in time, and that provides an ability to customize, or tailor, variation generation as closely as possible to an individual student or to a particular skill-level.